Alert archive / Montana / Tornado Warnings in 1999

Tornado Warning 3, NWS Great Falls, MT

August 14, 1999Fergus County, Montana

NWS Great Falls, MT issued this tornado warning at Aug 14, 1999, 5:10 PM MDT for Fergus County, Montana. It was in force for 35 min. 1 report came from inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties, with what was reported inside it.

The facts

Issued: Aug 14, 1999, 5:10 PM MDT (23:10 UTC)
Expired: Aug 14, 1999, 5:45 PM MDT
In force: 35 min
Issued by: NWS Great Falls, MT
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Fergus County, MT

The radar

The Billings radar (KBLX), 157 km from the middle of the area, began a volume at 23:09 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Aug 14, 5:15 PM MDT	Tornado F2	Lewistown, MT	NUMEROUS HAIL REPORTS 1 TO 2 INCHES...ONE WIND ESTIMATE AHEAD OF TORNADO 87KT

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 14, 4:15 PM MDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 11.2 hours before the alert went out and 103 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1458 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 21 m²/s²
0-3 km storm-relative helicity: 66 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KTFX 142312 RRA
TORGTF
MTC027-142345-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
510 PM MDT SAT AUG 14 1999

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* TORNADO WARNING FOR...
  CENTRAL FERGUS COUNTY IN MONTANA

* UNTIL 545 PM MDT

* AT 507 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  THUNDERSTORM WITH A POSSIBLE TORNADO OVER CENTRAL FERGUS COUNTY...
  OR ABOUT 5 MILES NORTHEAST OF LEWISTOWN...MOVING NORTHEAST AT 5
  MPH.

DO NOT USE YOUR CAR TO TRY TO OUTRUN A TORNADO. CARS ARE EASILY
TOSSED AROUND BY TORNADO WINDS. IF YOU ARE CAUGHT IN THE PATH OF A
TORNADO...LEAVE THE CAR AND GO TO A STRONG BUILDING. IF NO STRUCTURE
IS NEARBY...SEEK SHELTER IN A DITCH OR LOW SPOT.

THE SAFEST PLACE TO BE DURING A TORNADO IS IN A BASEMENT. GET UNDER A
WORKBENCH OR OTHER PIECE OF STURDY FURNITURE. IF NO BASEMENT IS
AVAILABLE...SEEK SHELTER ON THE LOWEST FLOOR OF THE BUILDING IN AN
INTERIOR HALLWAY OR ROOM SUCH AS A CLOSET. USE BLANKETS OR PILLOWS TO
COVER YOUR BODY AND ALWAYS STAY AWAY FROM WINDOWS.

IF IN MOBILE HOMES OR VEHICLES...EVACUATE THEM AND GET INSIDE A
SUBSTANTIAL SHELTER. IF NO SHELTER IS AVAILABLE...LIE FLAT IN THE
NEAREST DITCH OR OTHER LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS.

LAT...LON 4713 10952 4700 10934 4724 10893 4740 10916

$$

BRUSDA

What forecasters said that day

The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Great Falls, MT wrote its last area forecast discussion before this tornado warning went out at Aug 14, 2:45 PM MDT, 2 hours 25 minutes earlier.

Area forecast discussion, Aug 14, 2:45 PM MDT, 2 hours 25 minutes before

SOUTHWEST AND NORTH CENTRAL MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GREAT FALLS MT
245 PM MDT SAT AUG 14 1999

12Z MDL DATA SLOW TO ARRIVE. NGM AND AVN FAIRLY SIMILAR WITH MOST
DETAILS OF UPR TROF MOVG E. SAT IMAGERY INDICATES UPR LOW OVR XTRM ERN
WA ATTM WITH A FAIRLY WELL DEFINED MSTR PLUME THRU N-CNTRL ID AND WRN
MT. SOME CNVTV ACTVTY ALRDY KICKING OFF OVR SW MT BUT TSTMS HAVE BEEN
WEAK. WL LEAVE HIGHEST POPS TGNT FOR SW AND NW PORTION OF CWA AND THEN
GO WITH HIGH POPS ACRS N-CNTRL MT SUN. AVN HAS WLY FLOW OVR CWA BY SUN
NGT WITH ANOTHER S/WV DROPPING INTO NW MT MON. COOLER AIR FOR SUN WITH A
SLGT WRMG MON. EMANUEL
GTF 5512 HLN 6423 HVR 5632

The office that day

Everything else NWS Great Falls, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 14, 4:57 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	48 min
Aug 14, 5:21 PM MDT	Severe Thunderstorm Warning	TFX	Chouteau	39 min
Aug 14, 5:38 PM MDT	Severe Thunderstorm Warning	TFX	Judith Basin	52 min
Aug 14, 5:45 PM MDT	Severe Thunderstorm Warning	TFX	Fergus	30 min

Nearby

Tornado Warnings in Montana, 1999 Every tornado warning in 1999 Tornadoes in 1999

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.